The replaceable gripper is held in place with a differential lock screw. The gripper can be replaced when worn or a different style gripper is required. The housing is made from alloy steel, heat treated to Rc 43/46 with black oxide finish. The parts listed below are for the housing unit and differential lock screw only and do not include a gripper. Grippers must be ordered separately. Use only with grippers that have a tapped through hole.